A heat source system for enabling the supply of chilled water of a constant temperature is provided in a factory equipped with a semiconductor fabrication facility or the like (for example, a clean room). As the heat source system, there is one equipped with a plurality of centrifugal chillers, as shown in PTL 1, for example.
In factories equipped with semiconductor fabrication facilities, high-temperature water of approximately 60 to 70° C. that is used as cleaning water in the semiconductor fabrication facility and medium-temperature water of approximately 32 to 45° C. for heating are required in addition to the chilled water.
Conventionally known heat source systems that supply such high-temperature water and medium-temperature water include, as shown in FIG. 7, those in which a boiler 129 is combined with a centrifugal chiller 101.
As shown in FIG. 7, the centrifugal chiller 101 is driven by an electric motor 103 and is equipped with a centrifugal compressor 105 that compresses refrigerant, a condenser 107 that condenses the refrigerant compressed by the centrifugal compressor 105, an expansion valve (not shown) that expands the refrigerant condensed by the condenser 107, and an evaporator 109 that evaporates the refrigerant expanded by the expansion valve.
The evaporator 109 is connected to chilled water piping 110, through which the chilled water flows, and the chilled water is cooled by the latent heat of evaporation of the refrigerant that is evaporated in the evaporator 109. The chilled water piping 110 is provided with a chilled water pump 112, and the chilled water is supplied in a circulating manner by this chilled water pump 112 between the evaporator 109 and external loads (not shown) that use the chilled water, such as the semiconductor fabrication facilities.
The condenser 107 is connected to cooling water piping 114, through which cooling water flows, and the latent heat of condensation of the refrigerant condensed in the condenser 107 is dissipated to the cooling water. The cooling water piping 114 is provided with a cooling water pump 116, and the cooling water is supplied in a circulating manner between a cooling tower 118 and the condenser 107 by this cooling water pump 116. The cooling tower 118 is of the type in which the cooling water is cooled by being sprinkled into the outside air by a sprinkler 120 and is equipped with a fan 119 for cooling the sprinkled cooling water.
The cooling water piping 114 located between the condenser 107 and the cooling tower 118 is provided with a medium-temperature-water heat exchanger 121. This medium-temperature-water heat exchanger 121 is provided with medium-temperature-water piping 125 that guides the hot water supplied from a medium-temperature-water pump 123. The medium-temperature water that has passed through the medium-temperature-water piping 125 and that has received heat from the cooling water in the medium-temperature-water heat exchanger 121 is guided to medium-temperature-water supply piping 127, and is used as the heat source for heating.
In order to supply high-temperature water, in addition to the centrifugal chiller 101, the boiler 129 is provided. The boiler 129 is provided with high-temperature-water piping 132 that guides feed water supplied from a boiler water supply pump 130. The feed water circulating in the high-temperature-water piping 132 is heated in the boiler 129 and is guided to high-temperature-water supply piping 134 as high-temperature water of approximately 60 to 70° C. The high-temperature water supplied by the high-temperature-water supply piping 134 is used as a heat source of high-temperature cleaning water for the semiconductor facilities. The reference numeral 136 is back-up piping that connects the high-temperature-water piping 132 and the medium-temperature-water supply piping 127, and that is used for supplying the high-temperature water as a back-up for the medium-temperature water.
FIG. 8 shows a heat source system in which a heat-recovery machine is employed for the condenser 107 in FIG. 7. Specifically, in FIG. 8, the heat source system is configured such that the medium-temperature-water piping 125 is connected to the condenser 107, and heating is conducted by a medium-temperature-water heat exchanger (not shown) in the condenser 107, thereby obtaining heat from the condenser 107. Therefore, in the heat source system shown in FIG. 8, the medium-temperature-water heat exchanger 121 shown in FIG. 7 is omitted. Because the other configurations are the same as in the heat source system shown in FIG. 7, the same reference numerals are assigned and descriptions thereof are omitted.